The erosion of beachfront property is a continuing problem which has been studied and surveyed for many years. The problem relates to beaches, man-made and natural channels, and other waterfront locations. The primary cause of erosion is fluid forces active in the region where water meets land, as at the beachfront. Exacerbating factors are the movement of higher velocity currents associated with waves, tides, storm surges and in some instances boat wakes.
A variety of revetment systems have been proposed to slow or prevent the loss of sand and earthen materials that occurs with erosion at beachfront locations. One such system that has been used on a limited scale utilizes large concrete wall assemblies. These structures, which are costly to construct, have been employed to protect small sections of beachfront. However, providing an adequate foundation for large concrete walls is difficult, and the catastrophic failure of these structures can result under the force of a major storm and the associated wave forces. Concrete walls are also susceptible over time to cracking, chipping, and erosion from wind, sand and water.
Other systems are known that utilize a layer of interlocking concrete tiles. This type of system forms a lining or mat of erosion controlling material which is intimately in contact with the underlying ground material. Due to the tendency of the concrete tiles or sections to lift when subjected to high velocity water flows and heavy wave forces, these systems are generally more appropriate for river and canal banks where the forces incident on the tiles are limited.
Durable materials used in traditional erosion control systems include marine wood, aluminum, and large stones known as rip-rap. Steel has also been employed but is typically susceptible to rust and quick deterioration. A number of traditional pier type constructions, made primarily of wood materials are also well known, but have generally been limited to structures in protected areas such as harbors and marinas.
A preferred material for the construction of traditional bulkheads, docks and marinas is marine pine. When not exposed to sun light and the damage caused by ultra violet (UV) light, this wood essentially resists deterioration over periods of hundreds of years, and may actually harden over time.
One capability not achievable in many of the revetment systems previously proposed is the ability of the structure to yield slightly and recover when subjected to forces of the kind encountered in beachfront areas. This capability is especially important during storms and heavy surf conditions. Fixed and very rigid structures, like those constructed with concrete slabs, may catastrophically fail under extreme conditions due to their rigidity. It is therefore desirable to provide a fixed, yet somewhat flexible, very tough structure for the construction of bulkhead walls and revetments.
A long known and constantly worsening problem, which is seemingly unrelated to beachfront property erosion, relates to the disposal of used vehicle tires. Composed of compositions comprising rubber, nylon and steel materials, used and worn tires are very resistant to natural decay and are virtually unaffected by sand, salt water, and UV light. The dilemma of how to dispose of used and worn tires has also been studied without satisfactory solution for many years. While beachfront use of tires has been proposed in some applications, no fully satisfactory erosion control solution has resulted. It would therefore be highly desirable to provide an environmentally safe way to recycle discarded vehicle tires, while at the same time providing an improved level of erosion control.
As the building of homes and other structures at the waters edge continues, there is a need for new and improved methods to construct revetment and bulkhead systems to slow or prevent the erosion of valuable beachfront real estate and the structures constructed thereon. Objects of the present invention are, therefore, to provide a new and improved bulkhead system having one or more of the following capabilities and features:
a simple method of construction with a resulting structure foundationally fixed and capable of absorbing wave and water forces typically found at beachfront areas;
environmentally safe recycling of used vehicle tires;
a high integrity bulkhead system with low materials and production cost when compared to alternative systems;
a very durable and long lasting structure, resistant to the effects of wind, weather, sunlight and salt or fresh water; and
moderate cost due to the use of materials which are readily available, recyclable, or both.